Tube-expander



- H. H. COLLINS.

Tube-Expanderl Fig. 2 is a vertical and UNITED STATES HENRY H. COLLINS,OF PITTSBURG, PENNSYLVANIA.

TUBE-EXPANDER.

SPECIFICATION forming part of Letters Patent No. 223,840, -dated January2'?, 1880.

Application led December 10, 1879.

To all whom, it may concern Beit known that I, HENRY Pittsburg, in thecounty of Allegheny and State ol' Pennsylvania, have invented a new anduseful Improvement in Tube-Expanders; and I do hereby declare that thefollowing is a full and exact description thereof, reference being hadto the accompanying drawings, and to the letters of reference markedthereon.

My invention relates io an improvement in tube-expanders, the same beingan improvement upon the tube expander of William Thomson, of Glasgow,Scotland, for which English Letters Patent were granted him April 24,-1874, No. 1,430, my improvement consist ing in placing the recesses forthe reception of the expanding-rollers at an acute angle to the axis ofthe mandrel.

To enable others skilled in the art to which myinvention is most nearlyconnected to make and use it, I will proceed to describe itsconstruction and operation. s

In the accompanying drawings, which form part of my specification,Figure l. is a side elevation of my improvement in tube-expanders.longitudinal section of the same at line x of Fig. 3. Fig. 3 isatransverse section of the same at line e of Fig. l. Fig. 4 is a sideview of one of the rollers.

In the accompanying drawings, A represents the mandrel,in which ispivoted a roller, B, journaled at gand h, and is held in position bymeans of screw-threads t' and screw-nut j, which is prevented fromturning by a pin, k, or by a jam-nut, as indicated by the dotted lines oin Fig. 1. The mandrel is made hollow and furnished with a number ofrecesses,

H. GoLLINs, of

D, which are arrangedY longitudinally at an acute angle to the axis ofthe mandrel A. In the recesses D are journaled, at e and f,taperingrollers O, the inner surfaces of which impinge on the roller B.The rollers O, at the end having the smaller diameter, are tapered at adifferent angle from that of the body of said rollers, as indicated at10.' By thus tapering the rollers G, as at p, a lead is formed for thebody of said rollers, and the forming of an inward-projectie g ridge isprevented.

By arranging the recesses D at an acute angle to the axis of the mandrelA, the bearing ends of the rollers C will be at an acute angle to theaxis of the roller B, whereby the desired feedof the expander isobtained and :all undue strain and friction ofthe journals c andj of therollers C is avoided, causing the expander in all its parts to worksmoothly in the operation of expanding the tube. The ends of thejournals c of the rollers G are covered by cap-piecel,wl1ich is held inposition by the journal h of the roller B and the vscrew-nut j, 6o asshown in Figs. 1 and 2.

The operation of my improvement is as follows: The tube being placed inthe boiler-head in the usual manner, the small end of the expander isplaced in the end of the tube. The operator then places a wrench uponthe end q of the roller B, and turning it to the right will cause therollers C to turn to the left, the outer surface of the rollersimpinging upon the inner walls of the tube, and their inner 7o surfaceimpinging upon the rolle-r B, the latter, B, revolving the former, C, byfrictional or tractional action of `the one upon the other. Theinclination of the rollers C with relation to the axis of the mandrel A,the latter acting as a guide, feeds the expander into the tube, therollers C performing the function of a series of screw-threads. When theexpander has entered the tube sufficiently to give it the desiredexpansion, the operator 8o places a wrench upon the square o on themandrel A, turning it sufficiently to release the expander in the tube,which is then withdrawn. The roller B may be turned through the mediumof levers, as indicated by the dot- 8 5 ted lines n, (shown in Fig. 1,)placed in the opening m.

The advantage of my improvement consists in avoiding lfriction upon thejournals of the rollers G by arranging them in the manner as 9ohereinbefore described and giving to the part of the rollersO adifferent angle or taper from that of the body, said tapers forming alead for the body of the rollers, and preventing the formation of ridgesupon the inner walls of the tube, which is a very important feature, forsuch ridges form impediments to a free y draft and catch fine particlesof fuel, which, becoming ignited, unduly heat the iiues around saidridges, causing a wasting and de- Ioo struetive action, which soondestroys the tube; In a tube-expander, the combination, with and byarranging the angles of force of the the roller B, ofthe mandrel A,provided with rollers C with relation to the axis of rotation recessesD, for the reception ofthe expandingof the roller B and mandrel A, theexpander rollers, arranged at an acute angle with rela- I5 5 as a Wholewill Work smoothly, and Without tion to the axes of said mandrel androller B,

any dragging and undue frietional action upon substantially as and forthe purpose set forth.

the inner Wall of the tubing in the process of T expanding it. l HENRXH. COLLINS.

Having,1 thus described the nature, eonstrue- Witnesses:

I e1ai1nis- DE WITT C. ALLEN.

1o tion, and operation of my improvement, what JAMES J. JOHNSTON,

